The invention relates to a water cleaner in which the operator can easily regulate the quantity of a detergent which is dispensed in relation to a quantity of water delivered.
In the field of equipment and spray-guns for water-cleaners, the prior art teaches application downstream of the gun of devices for injecting a predetermined dose of detergent into the water.
These devices aspirate detergent from a special container employing a Venturi-type effect, in which a depression is created in an expansion chamber as a result of the velocity of the water pumped by the cleaner.
The prior art also includes devices enabling a regulation of the delivery of the detergent, i.e. a change in ratio between aspirated detergent delivery and water delivery.
These known devices are generally constituted by a calibrated nozzle inserted in the detergent aspiration conduit, the nozzle being interchangeable. Thus by changing the nozzle the detergent flow rate is also changed.
Other known detergent dispensers with regulatable delivery include a vacuum-breaker valve on the expansion chamber. The vacuum-breaker can be calibrated, so the degree of vacuum can be varied in the expansion chamber and therefore the aspirated detergent fluid can also be regulated.
The above-described devices present various drawbacks. Firstly, the nozzles inserted on the detergent aspiration conduit are subject to blockages during operation, reducing or even interrupting delivery of the detergent.
Further, it is a nuisance to have to substitute the nozzle according to the detergent and flow rate required, as it involves having replacement nozzles to hand, which is not always the case with water cleaning apparatus.
Finally, it is not immediately obvious which nozzle is installed due to poor legibility from the outside, so the flow rate ratio, i.e. the ratio between the detergent and water delivery, is not evident unless the nozzle is first dismounted and/or replaced.
In the case of regulation devices equipping vacuum-breaker valves, there is a risk of blockage or loss of accuracy, but especially there is a lack of precision in determining the exact value of the desired dispensing ratio.